Gujarati is the most common first language after English, with 1,568 speakers, followed by Punjabi and Urdu.

Irish Gaelic, Maltese and African dialects Ndebele, Bemba and Efik-Ibibio are among the unusual first languages spoken in the county's classrooms.

Children whose first language is English are in the minority in nine schools in Preston.

The figures, uncovered following a Freedom of Information Act request, come as it also emerged that more than half the pupils in 25 of Lancashire's schools do not speak English as their first language.

Almost 10% of primary pupils and 6.5% of secondary students are not native English speakers, Government figures show. Teaching unions have warned schools with large numbers of non-English speakers that they may need extra funding to help them meet academic targets.

Pat Probin, Preston secretary of the National Union of Teachers, said: "It's unfair of the Government to judge primary schools who have children coming in with no English in the same way they assess schools who have no non-English speakers."

Mick Brookes, general secretary of the Association of Teachers and Lecturers, stressed that schools welcomed new arrivals but said they often lacked resources to integrate them properly.

Fulwood High School and Arts College in Preston is Lancashire's most diverse school, with 19 different first languages spoken – including Arabic, Swedish and Somali.

Deepdale Infants School, also in Preston, has 16 first languages and almost nine in 10 pupils do not have English as their mother tongue.

Nationally, more than 800,000 school children do not speak English as their first language, according to official figures from the Department for Children Schools and Families.

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